Spatially-heterodyned holography

Abstract

A method of recording a spatially low-frequency heterodyne hologram, including spatially heterodyne fringes for Fourier analysis, includes: splitting a laser beam into a reference beam and an object beam; interacting the object beam with an object; focusing the reference beam and the object beam at a focal plane of a digital recorder to form a spatially low-frequency heterodyne hologram including spatially heterodyne fringes for Fourier analysis; digital recording the spatially low-frequency heterodyne hologram; Fourier transforming axes of the recorded spatially low-frequency heterodyne hologram including spatially heterodyne fringes in Fourier space to sit on top of a heterodyne carrier frequency defined by an angle between the reference beam and the object beam; cutting off signals around an origin; and performing an inverse Fourier transform.

1. A method of recording spatially low-frequency heterodyne hologram including spatially heterodyne fringes for Fourier analysis, comprising:
 splitting a laser beam into a reference beam and an object beam; 
 interacting the object beam with an object; 
 focusing the reference beam and the object beam at a focal plane of a digital recorder to form a spatially low-frequency heterodyne hologram including spatially heterodyne fringes for Fourier analysis; 
 digital recording the spatially low-frequency heterodyne hologram; 
 Fourier transforming the recorded spatially low-frequency heterodyne hologram including spatially heterodyne fringes and shifting axes in Fourier space to sit on top of a heterodyne carrier frequency defined by an angle between the reference beam and the object beam; 
 cutting off signals around an origin; and 
 performing an inverse Fourier transform. 
 
   
   
     2. The method of  claim 1 , further comprising reflecting the reference beam from a reference beam mirror at a non-normal angle. 
   
   
     3. The method of  claim 1 , wherein the Fourier transform is an extended Fourier transform. 
   
   
     4. The method of  claim 1 , wherein digitally recording includes detecting the beams with a CCD camera. 
   
   
     5. The method of  claims 1 , further comprising storing the spatially low-frequency heterodyne hologram as digital data. 
   
   
     6. The method of  claim 1 , further comprising replaying the spatially low-frequency heterodyne hologram. 
   
   
     7. The method of  claim 1 , further comprising transmitting the spatially low-frequency heterodyne hologram.